[Asterisk-Users] GSM win<>lin [was: Snom100 GSM]

Gary gary at ausmail.com
Fri May 16 08:42:00 MST 2003


On 16 May 2003 10:23:18 -0500, Steven Critchfield wrote:

>
>For those that either cross between linux and windows, be aware that the
>way GSM is represented is different. A GSM frame is 32.5 bytes. On
>Windows they place 2 32.5 byte frames together shifting the second frame
>down half a byte to make a 65 byte packet containing 2 frames. On unix
>systems, it is standard to just ignore the final 4 bits of the frame,
>and therefore we can transmit in 33 byte packets a frame and we don't
>use any bit shifting. I'm sure this is where most problems with GSM come
>from.


Ah, now thngs start to make sense, but the x-lite problem actually
exists win <>win as well (I believe).

Its funny how these things go in circles and how some handle it...

g711 works, but is expensive in terms of bandwidth,
gsm, better on bandwidth but some implementation problems.
g7...  etc etc

some talk of "new" codecs which goes back to compatibility problems...

thinking back on history now...

soft phones was to be all the go, yet how many rel solutions are out
there, machines have got faster etc, but the os (i am refering to m$)
makes things sower etc (bloatware).

hardphones really haven't taken off so much yet either and really only
recently has affordable ip solutions become available.

Comes back to my 4 steps mentions in another thread.....

finally: whats our biggest problem ?? comes down to M$ doesn't it ?? 
:-(
.






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